Exposure control device for flashlight equipped camera

ABSTRACT

A camera for taking pictures with the aid of a flashlight carries a member coupled to the exposure meter indicator for moving a control lever which changes the lens aperture of the camera in accordance with the brightness of the object being photographed.

[ Feb. 15, 1972 United States Patent Fukuda [56] ReierencesCited UNITEDSTATES PATENTS 3,443,496 5/1969 Sauer et al.

[54] EXPOSURE CONTROL DEVICE FOR ELASHLIGHT EQUIPPED CAMERA SusmuFukuda, Nishinomiya-shi, Japan [73] Assignee: Fuji Photo Film Co., Ltd.,Kanagawa,

[72] Inventor:

3,464333 9/1969 Aokietal.....

3,492,928 2/1970 Kitai............. 3,515,047 6/1970 Hahn...

Japan Oct.28, 1969 A 211 Appl.No.: 870,031

3,529,524 9/1970 Veda.......................

[22] Filed:

Primary Examiner-Joseph F. Peters Attorney-Sughrue, Rothwell, Mion, Zinn& Macpeak [30] Foreign Application Priority Data Nov. 27, 1968 [57]ABSTRACT A camera for taking pictures with the aid of a flashlightcarries a member coupled to the exposure meter indicator for moving acontrol lever which changes the lens aperture of the camera inaccordance with the brightness of the object being photographed.

CMA 0 4 1.7 lb 1 %3R s 4 AC6 M C 0 5 9 H 5 u 9 Field f C 8.. Um I] 21 55[l 6 Claims, 1 Drawing Figure I PATENTEUFEB 15 I972 mvmoa FUKUDA SUSUMUI'w MI ATTORNEYS EXPOSURE CONTROL nnvrcr: FOR rLxsrrucrrir EQUIIPEDCAMERA BACKGROUND OF THE INVENTION 1. Field of the Invention Thisinvention relates to the novel exposure control device for controllingthe size of the lens aperture of the camera under flashlightconditionsand more particularly to an exposure control device whichcontrols thesize of the lens aperture in'accordance with the distance between thecamera and the object being photographed.

2. Description of the Prior Art K r In' conventional automatic exposurecontrolling cameras employing electric photoconductors, film exposure isauto- 'matically controlled only when the brightness. of the objectbeing photographed is above a predetermined minimum value. Where thebrightness is insufficient for the photoconductor to automaticallycontrol the exposure, the exposure of the film must be controlledmanually.

SUMMARY OF THE INVENTION I The present invention provides an exposurecontrol device BRIEF DESCRIPTION OF THE DRAWING The single FIGURE is aperspective view of one embodiment of the exposure control device inaccordance with the present invention as applied to aconventional"photographic camera.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the drawing, acontrol lever 2 is of T-shaped configuration and is pivotally disposedwithin the camera body (not shown) for controlling the size of the lensaperture of the camera. The control lever 2 is provided at one end witha pin 21 which engages slots 11 of respective diaphragm blades arrangedin a. lens system 100. The pair of diaphragm blades 10 are pivotallymounted at one end, in this case positioned to pivot about an axis justabove pin2l. The other end of the T- shaped control lever 2 terminatesin a slightly bent portion 22' which is selectively brought intoengagement with the stepped endv 42 of control member 4 when theillumination on the object is insufiicient for photographing the samewithout operating the flashlight associated with the camera. In thisrespect, the stem portion 23- of the control lever 2 is so positionedthat it moves into engagement with member 3 to achieve automaticexposure control in the absence of energization of the flashlight. Toprovide this dual, automatic control, a gap is provided between the stemportion 23 and'meimber 3 as indicated in the drawing. In the embodimentillustrated in the drawing, the size of the lens aperture is determinedby the pair of diaphragm blades 10, and increases in response to thecounterclockwise rotation of the T-shaped lever 2. The T-shaped lever ismounted for rotation intermediate of its ends and movablecounterclockwise as shown by the arrow. The size of the lens aperture,of course, decreases under clockwise rotation of the same element.

sure meter 200 and to position the lever 2 and tothereby control thesize of the lens aperture by opening and closing the two blades 10 toprovide the correct exposure of the film (not shown).

The control member 4 is pivotally mounted by means of pivot pin 40 and:is biased to rotate counter clockwise about the pin 40 by means ofspring 41. The control member 4 operates only when the brightness of theobject being photographed is so dark that flash lighting is required. Asmentioned previously, the upper end 42 of the control member 4 isstepped while the lower portion 43 is slightly curved. The member 4 isfurther provided with a laterally extending branch portion 44. Thestepped end 42 of the control member is normally located out of therange of movement of the right angle bent portion 22 of control lever 2.Control member 4 is prevented from rotating counterclockwise by means ofstop 5 which is so positioned as to be in contact with the lower edge ofthe branch portion 44. Clockwise rotation of control member 4 is limitedby a movable pin 6 which varies its position with respect to pivotablecontrol member 4 in accordance with he the between the camera and theobject. A lever 7 is pivoted about its center and so disposed such thatone end is in contact with the upper edge of the branch portion 44,beyond stop 5. The other end of lever 7 is in contact with theflashlight switching member 8. One end 81 of the flashlight switchingmember 8 is associated with the exposure meter 200 to sense its needle20l'in'such a manner that the switching member 8 moves downwardly asindicated by the arrow in response to an indication of the exposuremeter that the brightness of the object being photographed is too darkto provide the desired exposure without additional lighting such as bythe flashlight. The arrangement for causing the switching lever is tomove downwardly is constructed quite easily in accordance with prior artteachings, e.g., the member 8 may be connected directly to the pointerof an exposure meter such that the member movesdownwardly in response tomovement of the pointer when the pointer moves out of the definite range(where the camera has the ability to take the picture without thenecessity for additional illumination). When the switching member 8moves downwardly, the lever 7 is pivoted clockwise as shown by the arrowwhereby, control member 4 rotates clockwise under the bias of spring 41.

Thus, the control member 4 moves into engagement with control lever 2 tocontrol movement of the same when the objecting being photographed is sodark that it requires auxiliary illumination as from a flashlight. Wherethe control member 4 rotates clockwise, through only a small angle, thebent portion 22 of control lever 2 moves into engagement with thestepped end 42 of the control member. The extent of the inclination orrotation of control member 4 is determined by the position of pin 6which changes depending upon the distance between the camera and theobject being photographed. Thus, the bent portion 22 of lever 2 may bebrought into engagement with difi'erent stepped surfaces of the steppedend 42 of control member 4, in accordance with the distance between theobject being photographed and the camera. In this respect, the pin 6 maybe connected directly to a distance adjustment ring (not shown) carriedby the camera. In the drawing, the mark P indicates the position of pin6 for taking portrait pictures, the position G in dotted lines indicatesthe position of pin 6 when taking group pictures. The dotted lineposition of the pin 6 identified as infinity is employed when takingpictures where the object is at extremely long range. The distance adjustment ring (not shown) may be operated either manually orautomatically. Correspondingly, in the embodiment shown in the drawing,the lower step F8 corresponds to position P, the central step'F16corresponds to the intermediate position G for the pin and the higheststep corresponds to the infinity pin position.

For flashlight photography, switching member 8 moves down to an extentcausing lever 7 and control member 4 to rotate clockwise while member 3moves up so as to move into contact with the lower edge of step portion23 of lever 2. Therefore, when the member 3 begins to move lever 2, the

. bent portion 42 of the control lever 2 with stepped portion 42 of thecontrol member 4, the size of the lens aperture is thus determined. Thecamera can be so arranged that energization of the flashlight (carriedby the camera or separately) may be achieved only at the moment when theshutter is operated and only when the control member 4 is inclined tothe extent that it engages the bent portion 22 of the control lever 2 byan arrangement in which either the control member 4 or lever 7 iscoupled to the flashlight operation means. Thus, the flashlight may beautomatically operated and a "correct exposure may be obtained when theobject requires a flashlight as auxiliary illumination because of thedarkness of the object being photographed.

It is not always necessary that the lower portion of the control memberbe curved. If desired, the lower portion 43 of the control member 4 maybe straight, and pin 6 moves along a straight line path. In this case,the shape of the lower portion of the control member 4 depends upon theshape of the path of movement of pin 6 between positions P, G andinfinity.

What is claimed is:

1. In ,a camera including an exposure meter, a lens system, lensaperture controlling means, a control lever coupled to said lensaperture controlling means, and means for normally operating saidcontrol lever automatically in response to illumination of the objectbeing photographed, the improvement comprising: an exposure meter, acontrol member pivotably mounted and movable between a first positionand a second position wherein, at said second position, a stepped end ofsaid control member engages said control lever, means for biasing saidcontrol member into engaging position with said control lever, a levercoupled to said exposure meter operated member of normally preventingsaid control member from pivoting into engagement with said controllever, and a member operatively coupled to said exposure meter formoving said control member to said second position to cause said controllever to modify the position of said lens aperture controlling meansindependently of said first control means.

2. The camera as claimed in claim 1 further comprising a movable pinpositioned in the path of movement of said control member fordetermining which step of said control member engages one end of saidcontrol lever, and means for variably positioning said pin at positionscorresponding to the distance from the camera to the object beingphotographed.

3. The camera as claimed in claim 2 whereinsaid lens aperture controlmeans comprises a pair of pivoted diaphragm blades, said control leveris T-shaped in configuration and is pivoted intermediate of its ends,one end of said control lever includes a pin and slot means forengagement with said diaphragm blades for controlling movement of thesame about the diaphragm blade pivot axis, said first control meanscomprises a member movable into engagement with said control meansbetween said lever pivot axis and said pin and slot means, wherebyengagement between the end of said control member and the other end ofsaid control lever modifies movement of said diaphragm under operationof said first control means.

4. The camera as claimed in claim 1 wherein said control member includesa lateral extension in contact with the fixed stop for limiting movementof said control member out of the path of said control lever, and saidcamera further includes a pivoted lever operatively coupling saidexposure. meter coupled member to said control member and normallyoperating to prevent movement of said member into contact with the endof said control lever, said exposure coupled member adapted to pivotsaid lever to allow selective engagement between said control member andthe end of said control lever opposite that coupled to said diaphragmblades.

5. The camera as claimed in claim 4 wherein the end of said controlmember engaging said control lever is stepped, and

said camera further includes a pin movable in accordance with thedistance from the camera to the ob ect being photographed to control theextent of movement of said control member upon release by said pivotablelever to determine which step the end of said control lever engages.

6. The camera as claimed in claim 5 further including aflashlight-operating member and means responsive to pivoting of saidpivotable lever under action of said exposure meter control member foractuating said flashlight-operating member.

1. In a camera including an exposure meter, a lens system, lens aperturecontrolling means, a control lever coupled to said lens aperturecontrolling means, and means for normally operating said control leverautomatically in response to illumination of the object beingphotographed, the improvement comprising: an exposure meter, a controlmember pivotably mounted and movable between a first position and asecond position wherein, at said second position, a stepped end of saidcontrol member engages said control lever, means for biasing saidcontrol member into engaging position with said control lever, a levercoupled to said exposure meter operated member of normally preventingsaid control member from pivoting into engagement with said controllever, and a member operatively coupled to said exposure meter formoving said control member to said second position to cause said controllever to modify the position of said lens aperture controlling meansindependently of said first control means.
 2. The camera as claimed inclaim 1 further comprising a movable pin positioned in the path ofmovement of said control member for determining which step of saidcontrol member engages one end of said control lever, and means forvariably positioning said pin at positions corresponding to the distancefrom the camera to the object being photographed.
 3. The camera asclaimed in claim 2 wherein said lens aperture control means comprises apair of pivoted diaphragm blades, said control lever is T-shaped inconfiguration and is pivoted intermediate of its ends, one end of saidcontrol lever includes a pin and slot means for engagement with saiddiaphragm blades for controlling movement of the same about thediaphragm blade pivot axis, said first control means comprises a membermovable into engagement with said control means between said lever pivotaxis and said pin and slot means, whereby engagement between the end ofsaid Control member and the other end of said control lever modifiesmovement of said diaphragm under operation of said first control means.4. The camera as claimed in claim 1 wherein said control member includesa lateral extension in contact with the fixed stop for limiting movementof said control member out of the path of said control lever, and saidcamera further includes a pivoted lever operatively coupling saidexposure meter coupled member to said control member and normallyoperating to prevent movement of said member into contact with the endof said control lever, said exposure coupled member adapted to pivotsaid lever to allow selective engagement between said control member andthe end of said control lever opposite that coupled to said diaphragmblades.
 5. The camera as claimed in claim 4 wherein the end of saidcontrol member engaging said control lever is stepped, and said camerafurther includes a pin movable in accordance with the distance from thecamera to the object being photographed to control the extent ofmovement of said control member upon release by said pivotable lever todetermine which step the end of said control lever engages.
 6. Thecamera as claimed in claim 5 further including a flashlight-operatingmember and means responsive to pivoting of said pivotable lever underaction of said exposure meter control member for actuating saidflashlight-operating member.